Prospects for CP violation and rare decays at ATLAS and CMS.

The LHC experiments will perform sensitive tests of physics beyond the Standard Model (BSM). Investigation of B hadrons decays represents an alternative approach to direct BSM searches. ATLAS and CMS concentrate on B decays that can be registered by di-muon signature already at first trigger level. B-hadrons decaying to Jpsi-mumu will statistically dominate B-physics analysis allowing high precision measurements, in particular a test of BSM effects in the CP violation of Bs-Jpsiphi. In rare B decays ATLAS and CMS concentrate on a family of semi-muonic exclusive channels, b-smumu, and on purely muonic decay Bs-mumu. In 3 years at luminosity several units of 1033 cm-2 s-1, corresponding to 30 fb-1, each of these two experiments can measure the Bs-mumu signal with the 3 sigma significance, supposing SM value for a decay probability.